MCP Server: com.moltlinestudio/shipping

This MCP server implements a thin, dependency-free stdio bridge to Moltline Studio’s fleet of 22 hosted MCP servers. It is designed for MCP clients that only support the stdio transport, proxying newline-delimited JSON-RPC between the client and hosted server verbatim.

🛠️ Key Features

Computes dimensional weight, parcel fit, landed cost, and freight class
Free access note: 4 of 6 tools are free
Implements Model Context Protocol (MCP) with stdio bridge behavior
Proxy behavior is described as no telemetry and no dependencies beyond Python 3.9+ standard library

🚀 Use Cases

Freight and parcel calculations covering dimensional weight, parcel fit, landed cost, and freight class
Integrations where the MCP client requires stdio transport instead of Streamable HTTP

⚡ Developer Benefits

Avoids installing the hosted service when using the bridge for stdio-only clients
Verbatim JSON-RPC proxying: forwards newline-delimited JSON-RPC without modification

⚠️ Limitations

Acts as a bridge to hosted servers rather than a standalone computation service
Only supports clients that use the stdio transport

moltline-mcp

A thin, dependency-free stdio bridge to Moltline Studio's fleet of 22 hosted MCP servers.

Most modern MCP clients can connect to the fleet directly over Streamable HTTP — no install needed (see Direct connection below). This bridge exists for clients that only speak the stdio transport: it proxies newline-delimited JSON-RPC between your client and the hosted server, verbatim, with no telemetry and no dependencies beyond the Python 3.9+ standard library.

160 tools across 22 servers; 110 are free.
Free tier: no registration, no account, no credentials — connect and call tools immediately.
Premium tools are unlocked with a Moltline license. Set MOLTLINE_LICENSE in your MCP client's environment; the bridge sends it as the X-Moltline-License header and never writes it to argv, URLs or logs. See auth.md.
Independently checked by MCPize on the direct endpoints (scans of 5–6 September 2026: 6 A+, 15 A, 1 B+; scores 89–98). All 22 servers score 100 on clarity, 100 on reliability and 100 on trust, 95 on protocol and 87 on safety; the one finding raised on every server is that the free tier accepts anonymous access — which is the point of it — and the spread between servers sits in MCPize's "Market" dimension (a crowded category). Each server's MCPize listing links its own public result.

Find it on: Smithery · MCPize · Glama · Clawmart · MCP Registry

The fleet

Server	Tools	What it does
`catalog`	10	Search 138 agent skills and personas by plain-language job; preview any product.
`codereview`	7	Risk-scan a diff, flag AI-generated-code tells, find secrets, report complexity.
`govern`	8	Audit an MCP config or SKILL.md for over-broad scope and prompt-injection risk.
`timeops`	5	Business days, meeting overlap, recurrence expansion, deadline and SLA math.
`data`	7	Paste-your-data analytics: CSV profiling, A/B tests, correlation, growth, cohorts.
`humanizer`	5	Find AI-isms with evidence, fingerprint a writing voice, measure burstiness.
`business`	8	30 finance, bookkeeping, legal-ops and SMB operations persona-skill products.
`creator`	8	20 blogging, brand-voice, copywriting, video and social persona-skill products.
`educator`	7	8 curriculum, classroom, accommodations and exam-prep persona-skill products.
`outbound`	8	7 outreach, sequencing, deliverability, call-coaching and CRM-hygiene products.
`personal`	9	20 inbox, calendar, travel, meals and family-logistics persona-skill products.
`research`	8	7 research navigation, thesis, note-taking and citation persona-skill products.
`skillmd-lint`	6	Lint a SKILL.md for frontmatter, structure, secrets and size. All tools free.
`merchant`	6	Commerce arithmetic: processor fees, charge-to-net, invoice totals, proration.
`shipping`	6	Dimensional weight, parcel fit, landed cost, freight class, rate cards.
`shopify`	6	Check a product CSV, URL handles, variant matrices and metafield keys.
`dropship`	6	Dropshipping unit economics: margin, lead time, SKU mapping, price ladders.
`recall`	6	A portable knowledge-graph memory you pass in and get back. No database.
`vision`	6	Image header probing, bbox conversion, resize plans, color and detection math.
`regclock`	9	Incident-reporting deadlines from the legal text (EU CRA, NIS2, DORA, GDPR, UK GDPR, HIPAA, SEC 8-K), cited.
`taxlots`	8	Crypto cost basis: parse exchange CSVs, lint, match transfers, FIFO/LIFO/HIFO lots, Form 8949 rows, 1099-DA diff.
`optimize`	11	OR-Tools routing, 3-D packing, 1-D/2-D cutting, knapsack and shift rostering with stated limits.

Machine-readable discovery: api-catalog · per-server card at https://mcp.moltlinestudio.com/<server>/.well-known/mcp/server-card.json · fleet health.

Direct connection (preferred)

If your MCP client supports Streamable HTTP (Claude Desktop, Claude Code, Cursor, and most current clients do), point it straight at the hosted endpoint — nothing to install:

json

{
  "mcpServers": {
    "moltline-timeops": {
      "type": "http",
      "url": "https://mcp.moltlinestudio.com/timeops"
    }
  }
}

Swap timeops for any slug in the table above.

The stdio bridge (for stdio-only clients)

Install

Run directly (recommended) — the bridge is a single stdlib-only file, so a clone is all you need:

bash

git clone https://github.com/GarphenGate/moltline-mcp.git
python3 moltline-mcp/moltline_mcp.py timeops   # any of the 22 slugs; default: catalog

Docker — see Docker below if you prefer a container.

A PyPI package is planned; until then, use the methods above.

Client configuration

Point your MCP client at the script with an absolute path:

json

{
  "mcpServers": {
    "moltline-timeops": {
      "command": "python3",
      "args": ["/absolute/path/to/moltline-mcp/moltline_mcp.py", "timeops"]
    }
  }
}

Or run it through Docker (after docker build -t moltline-mcp .):

json

{
  "mcpServers": {
    "moltline-timeops": {
      "command": "docker",
      "args": ["run", "-i", "--rm", "moltline-mcp", "timeops"]
    }
  }
}

CLI

text

python3 moltline_mcp.py [server] [--timeout SECONDS] [--list] [--version]

server — one of the 22 slugs (default catalog); anything else fails fast with the valid list.
--timeout — per-request timeout in seconds (default 300, or env MOLTLINE_TIMEOUT).
--list — print the server slugs and exit.
Env MOLTLINE_BASE_URL — override the fleet base URL (for testing).
Env MOLTLINE_LICENSE — your Moltline license, sent as the X-Moltline-License header to unlock premium tools. Omit it and the bridge runs free-tier only.
Env MOLTLINE_DEBUG=1 — diagnostic logging on stderr (stdout stays protocol-clean). The license is never logged; debug output reports only whether one is configured.

Docker

The bridge also runs containerized (stdio in, network egress to the fleet required):

bash

docker build -t moltline-mcp .
docker run -i --rm moltline-mcp timeops   # any of the 22 slugs; default: catalog

See Client configuration for the matching mcpServers entry.

How it works

One process per server connection. Each JSON-RPC message read from stdin is POSTed to https://mcp.moltlinestudio.com/<server>; JSON and SSE-framed responses are relayed back to stdout as newline-delimited JSON. The bridge tracks the server-assigned Mcp-Session-Id and echoes the negotiated MCP-Protocol-Version, per the Streamable HTTP transport spec. It never inspects, stores, or reports your traffic.

Tests

The bridge ships with an offline test suite - no network, no dependencies:

bash

python -m unittest -v

Twenty-two tests cover the parts that actually break in a transport bridge: newline-delimited framing, SSE event splitting (multiple events, multi-line data: payloads, a trailing event with no blank line, comments and named events), session-id capture and reuse, protocol-version negotiation on initialize only, and error relay - a JSON-RPC error document is passed through verbatim, anything else becomes a well-formed -32603. CI runs them on Python 3.9, 3.12 and 3.13, plus a Docker build and container smoke test.

Access and licensing

Free tier — anonymous. No registration or credentials; all free tools work immediately.
Premium — unlocked with a Moltline license purchased (human-in-the-loop) at moltlinestudio.com. Set MOLTLINE_LICENSE in the environment and the bridge forwards it as the X-Moltline-License request header. It is deliberately not a command-line flag: argv is world-readable through ps. It is never placed in a URL and never logged. Details: auth.md.

length	number	required	Longest side of the packed parcel, in inches (or centimetres when using a metric divisor). Must be greater than 0.
width	number	required	Second side, same unit as length. Must be greater than 0.
height	number	required	Third side, same unit as length. Must be greater than 0.
actual_weight	number	required	Scale weight in pounds (or kilograms with a metric divisor). Must be greater than 0.
divisor	string	optional	Which published divisor to apply. "ups_daily" is 139 and "ups_retail" is 166 cubic inches per pound, as UPS states them; "usps" is 166; the metric options are cubic centimetres per kilogram. Use "custom" to supply a contracted divisor.
custom_divisor	number	optional	Your contracted divisor, used only when divisor is "custom". Must be greater than 0 in that case.

item_length	number	required	Item's longest side, in inches. Must be greater than 0.
item_width	number	required	Item's second side, same unit. Must be greater than 0.
item_height	number	required	Item's third side, same unit. Must be greater than 0.
box_options	array	required	Candidate inner box dimensions, each a list of exactly three positive numbers, e.g. [[12, 9, 4], [14, 10, 6]].
padding	number	optional	Cushioning allowance added to every item side before the comparison, in the same unit. Default 1.0; use 0 for a bare fit.

unit_cost	number	required	Ex-works cost of one unit in your currency. Must be greater than 0.
quantity	integer	optional	Units in the shipment. Must be at least 1. Default 1.
freight_total	number	optional	Total freight and insurance for the whole shipment, not per unit. Default 0.
duty_pct	number	optional	Import duty as a percentage of goods value, e.g. 6.5. Default 0.
tax_pct	number	optional	Import VAT or GST as a percentage of goods plus duty plus freight, e.g. 20. Default 0.
other_fees	number	optional	Brokerage, port and handling charges for the shipment. Default 0.

length	number	required	Longest side of the palletised freight. Must be greater than 0.
width	number	required	Second side. Must be greater than 0.
height	number	required	Third side, including the pallet. Must be greater than 0.
weight	number	required	Gross weight including the pallet. Must be greater than 0.
units	string	optional	"in_lb" for inches and pounds, or "cm_kg" for centimetres and kilograms. Default "in_lb".

base_cost	number	required	Fixed cost per shipment before weight, e.g. pick, pack and label. Must be greater than 0.
cost_per_lb	number	required	Marginal cost per pound. Use 0 for a flat rate card.
bands_lb	array	required	Upper weight bound of each band in ascending order, e.g. [1, 2, 5, 10]. At least one band, each greater than 0.
margin_pct	number	optional	Margin added on top of cost, e.g. 25 for 25%. Default 0.
round_to	number	optional	Increment to round each published price up to, e.g. 0.5 or 1. Default 0.5.

Moltline Shipping Maths

MCP Server: com.moltlinestudio/shipping

🛠️ Key Features

🚀 Use Cases

⚡ Developer Benefits

⚠️ Limitations

Topics

dim_weight

parcel_fit

landed_cost

freight_class

rate_card

free_shipping_threshold

moltline-mcp

The fleet

Direct connection (preferred)

The stdio bridge (for stdio-only clients)

Install

Client configuration

CLI

Docker

How it works

Tests

Access and licensing

Links

License

Install

Remote endpoint

Related servers

gross_margin_pct	number	required	Gross margin on a typical order, e.g. 45 for 45%. Must be above 0 and at most 100.
ship_cost	number	required	What one shipment actually costs you to send.
current_aov	number	required	Your current average order value.
target_uplift_pct	number	optional	How far above current AOV you want the threshold set, to pull baskets up. Default 0, which returns break-even.